Strange bootstrap failure, possible memory corruption

[Volker Reichelt <reichelt at igpm dot rwth-aachen dot de>]

Since today I'm getting a bootstrap failure on i686-pc-linux-gnu with
mainline while building libiberty. The problem is hard to reproduce
since it vanishes if I use -save-temps :-(

/home/reichelt/Work/gccbuild/src-3.5/build/gcc/xgcc -B/home/reichelt/Work/gccbuild/src-3.5/build/gcc/ -B/home/reichelt/GCC/FARM/gcc-3.5-20040720/i686-pc-linux-gnu/bin/ -B/home/reichelt/GCC/FARM/gcc-3.5-20040720/i686-pc-linux-gnu/lib/ -isystem /home/reichelt/GCC/FARM/gcc-3.5-20040720/i686-pc-linux-gnu/include -isystem /home/reichelt/GCC/FARM/gcc-3.5-20040720/i686-pc-linux-gnu/sys-include -c -DHAVE_CONFIG_H -O2 -g -O2 -I. -I../../../gcc/libiberty/../include  -W -Wall -Wtraditional -pedantic ../../../gcc/libiberty/regex.c -o regex.o
In file included from ../../../gcc/libiberty/../include/xregex.h:26,
                 from ../../../gcc/libiberty/regex.c:197:
../../../gcc/libiberty/../include/xregex2.h:548: warning: ISO C90 does not support `static' or type qualifiers in parameter array declarators
In file included from ../../../gcc/libiberty/regex.c:651:
../../../gcc/libiberty/regex.c: In function `byte_compile_range':
../../../gcc/libiberty/regex.c:4550: warning: signed and unsigned type in conditional expression
../../../gcc/libiberty/regex.c:4560: warning: signed and unsigned type in conditional expression
../../../gcc/libiberty/regex.c:4560: warning: signed and unsigned type in conditional expression
../../../gcc/libiberty/regex.c: In function `byte_regex_compile':
../../../gcc/libiberty/regex.c:2321: internal compiler error: in avail_expr_eq, at tree-ssa-dom.c:3672
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://gcc.gnu.org/bugs.html> for instructions.
make[2]: *** [regex.o] Error 1
make[2]: Leaving directory `/Work/reichelt/gccbuild/src-3.5/build/i686-pc-linux-gnu/libiberty'
make[1]: *** [all-target-libiberty] Error 2
make[1]: Leaving directory `/Work/reichelt/gccbuild/src-3.5/build'
make: *** [bootstrap-lean] Error 2

I suspect there's some memory corruption caused by the preprocessor
and the compiler trips over it later. But that's only a wild guess.
See PR 16652 for details.

Is anybody else seeing this?

Regards,
Volker